This project is designed to define regulatory mechanisms of cell wall growth. Salmonella typhimurium and its mutants will be used. The inner and outer membranes will be resolved by gradient centrifugation and used as enzyme preparations to study steps in peptidoglycan and lipopolysaccharide synthesis. Mutations which alter these activities will be characterized with respect to their effects on the structure of the membrane, accumulation of biosynthetic intermediates, and possible genetic control over the enzyme activities in question. Attempts will be made to "solubilize" several of these enzymes to understand the environmental factors required for maximal function. Experiments will also be performed to define a reaction sequence in which protein is translocated from the cytoplasmic membrane to the outer membrane during growth. These studies pertain to the mechanism of Gram-negative pathogenesis and mechanisms of bacterial growth.